Rotary selector switch with bias



June 16, 1953 D. w. JOHNSON I 2,642,502

ROTARY SELECTOR SWITCH BIAS Filed Dec. 17, 1951 Patented June 16, 1953 ROTARY SELECTOR SWITCH WITH BIAS David W. Johnson, New Britain, Conn., assignor to The Arrow-Hart & Hegeman Electric Company, Hartford, Conn., a corporation of Connecticut Application December 17, 1951, Serial No. 261,934

7 Claims.

This invention relates to rotary selector switches of a'type that is locked in off position but may be unlocked and moved into an on or a neutral position by moving the control shaft axially and rotating it. More particularly, the invention relates to the foregoing type of switch having provision for biasing the contacts into neutral position after they have been unlocked and moved either into neutral or an on position.

The invention constitutes a further improvement upon or development of the invention described and illustrated in my prior Patents 2,451,224 and 2,451,225, issued on October 12, 1948. In these prior patents, the operation of the power contacts occurs when the control shaft is moved axially. In some instances this is not desirable or necessary and it is sufficient and desirable that the control shaft be biased rotatively into a neutral position from which it can be rotated at will into an on position without the necessity of axial movement of the shaft. Under these circumstances, it is desirable nevertheless that shaft movable axially and rotatively and which is locked in one position from which it can only be unlocked by moving the control shaft axially but wherein in another rotative position, the shaft is biased but can be moved rotatively against such bias for operating selected contacts.

Other objects and advantages of the invention will appear as it is described in connection with the accompanying drawing.

In the drawingf Fig. l is a side elevation view partly broken away and in section illustrating a switch embodying the principles of my invention;

Fig. 2 is a longitudinal section view taken along line 22 of Fig. 4 through the locking section with parts broken away;

Fig. 3 is an exploded perspective view of certain elements of the locking section;

Fig. 4 is a bottom plan view of the locking section.

Referring to the drawings, the switch is built in sections such as B and C from molded insulating base members which carry various conductive or functional parts. Operation of the device is by rotation of a shaft which passes through all the sections and carries a handle 22,

Section B may contain wire terminals, fixed and movable contact elements and cams for operating the contacts to establish connections in control circuits for machines and electrical apparatus of any sort.

Section C may contain parts for holding the movable elements and the switch shaft in various positions into which they may be moved, and for releasably locking them in certain angular positions thereof. This section may also contain the means for biasing the switch shaft rotatively in a particular position.

The functions and the elements of the several sections are interrelated and coordinated to cause the device to be locked in an off position, to be biased in a neutral position, and to be movable rotatively to an on position from the neutral position when the shaft is in one axial position and not returnable to the off position until the handle or control shaft is moved axially.

Each of the B sections embracing the contacts and mechanism for establishing control circuits comprise a substantially square body 50 of molded insulation. The body 50 is centrally apertured as at 500 to permit passage of the shaft 20 and to accommodate an operating cam member that is made of molded insulating material. A square sectioned sleeve 2| is mounted on and rotates with the shaft 20 and passes through the cam member which has a square opening for that purpose so that when the sleeve is rotated the cam will likewise be rotated. Each section also comprises electrical contacts such as 52, or 52, one of each pair of said contacts being spring biased to engaging position and arranged to be operated by a cam member 60 to a position in which the contacts are separated. In my prior patents, the cam 60 and sleeve 2| are oriented on the shaft so that rotation of the shaft in one direction will permit some contacts to engage while separating others and operation of the shaft in the opposite direction will cause a different arrangement of the closed and open contacts. In the present instance, however, one preferred embodiment includes cams which will cause the contacts all to be open in the off position of the switch. In a neutral position, next to the off position, one or more of a set of contacts 52 will be closed in one of the B sections. In another of the B sections the contacts 52 will be open in neutral position but will be closed when the shaft and the control cam therewith are rotated into a position past neutral. in the desired positions are accomplished by cre- The opening and closing of the contacts ation of raised surfaces upon the cam members at proper places in the same manner as in my prior Patent 2,451,224.

In order to bias the control shaft in a certain presses upon a washer 45 of insulating material on the reduced end 20a and, which in turn is pressed upon the back or bottom closure'plate" 41 of the switch housing. Thebottom plate 41 is I recessed for the passage therethrough of there-- duced end 200,.

. "m, The section C comprises a square block 90 of molded insulation having acentral opening for the reception of the shaft 20. At the outefifd of the block on a handle 22 is fixed upon theiend of the shaft 20. At the other end of the block 90,---t-he centraleopening; is genlarged for, an. appreciable depth providing. a large chamber sor recess -9I Mounted: in. it, is -a. substantially-circular: metaL-plataM-having an opening to receive the shaft 20. Radial extenslons--.- (not. visible) from the plate .88 engage in recesses in the wall of-the block. 90 to prevent rotation and to locate the plate. at the desired point as-heretofore. In orderto bias; the operatingsha'ftfzll intheiioffffposition, there is seated onthe' plateQBfi aspringoperating member. t0 5... having a. central opening which for part ofits depth:is}circularl.as at [2511 withradially. extending slots 1 051). 11Fg5r} theremainder of Litsddepth the 'eentral opening .is square section as amuse tol receive the end of the rectangular. pr sduare sleeve 2"I which -oper' ates the .cam'sfifl. Alonglthe ed'g e of fon'e-face. the. memberjl 0.5 is formed wlth spaced "recesses as at. I05d-,.the recesses -beingsymmetrically disposed. on ..opposite sides .of..fadiameter ,Iand. each being less .than l8'0' mext'em (a? time l v radially, extending abutment's 1052; at each end of-th'e. recesses. The .bl'ock"90 is recessed-in'its end face to provide a flat -face-which will liein a for themeceptionpf a spring lfll which lies.part, 1y ,ineach; of the complementary" recesses. .Two

springs I01. may .be.- provided, ...as shown. .The springs ..I.0I..are provided with fiaten'd'pieces I28.

which when. the. switch is inhormal. ,or roe: position; abut. the ends .of; the niches... .When the v square sleeveZ I vrotates, th'e m einber I05 and the Y cam 60 rotate withit as asuiiit," Such. rotation causes .the .abutmentsL-I 05e..to engagen an end. of each spring-and tolcompress the'j'spring's .101 .between the abutments'fl lfie and the. endsuof. the recesses in theblocklQIl. .Suchcondition is illusreis ielii I I To preventvturning thev shaft 20, from'f off. position toneutral or an operating position except when 'it.is pushed, a lock member I00 is seated in the housing 90 comprising anapertured plate stamped, from sheet metal with a series of armate. concentrically located-teeth I02, I02" etc. bent to extend paralleljtothe'. axis of, the shaft [,Within and"jnorma1ly. pressed against t'he bottom of, the lock member I00 is'a'key member 96 which may be driven upon oriotherwise fixed- 1y mounte'd on the shaft in any suitable mane ner. ".The key membercomprises a sheet metal" disc having a radially extending. finger 06x" 4 which is adapted to seat within one or another of the slots I03 between the teeth I02. The spring 44 pressing upon the shaft 20 normally maintains the key member with its extension 96m located in one or another of the slots thus preventing rotation of the shaft. Upon pushing the shaft, it moves axially andmarri-es the key member 96 and hence moves its extension 06a: out from between the teeth I02", I02 permitting rotation of the shaft. Also fixedly mounted upon the shaft are stamped sheet metal members having Wings 960. extending radially from the shaft indiametrically opposite positions and 'in register with the radial recesses I05b in the member I05. The. axial pushing of the shaft carries the wingstsfia into the recesses I05 so that upon rotationof the. shaft the member I05 will rotate with theshaft'20 causing thereby rotation oftheisq'uare sleeve and operation of the switch contact through rotation of the cam 60 as hereinbefore indicated., .+Rotation of..the.shaft in the direction of the arrow. in. Figs 3 .will cause. movement from folfiito neutral and then to an fon. position. .Inthe, exampledllustrated, the tooth I02 is one.half.the..width ofthe teeth I02 and I02" oneither side thereofsJIhus a large notch or space [021i (equal .to one half ..,a.tooth .width plusaspacing I03) is...provided betweenthe tooth I02 and'the tooth I02 whereasa smaller space I03 is left between'the teeth I02 and I02! such spacebeing approximately equal. .to the width of 'thefradi'al. extension Thus, when the .key member. 96 has its extension removed from the. notch I03 .by. axial movement of the switch shaft and is rotated under thelarge open notch ...II)2n as..the .shaft is rotated and is then axiallymoved, .the.springsllflT wvillieause the extension .9.6:r..to.. press .against the side..of .the. tooth (atthe rightin 3) .That isthe-neutral position..o;f the..sWitbh.-. Fromv that. positionthe switch canbe rotated. manually by..turning.the shaft 20.. and handle 22.-within..the. compass of the notch .I02 n;withoutthe necessity oiaxial movementcfthe shaft... Such...movementfrom the .neutral position in' thedirection. of the arrowuntiltheextension 9.5a: abutsthetooth I02 will cause the contacts 52' to close. This is an onf. position and may also be the vstartingposition for the switch-,If the handle-is now released, the switch will move'back to neutral position under the bias of the'springs IS'L. If the switch, ha1. d1e vandshaft furthermore are moved. or pushed axially, the bias of the springs. l 91, and M will carry the pajrtsbacl; to.fo1f position wherein the extension. 963: lies .within the notch In order to'limitthe movement of the switch to the three positions just; mentioned namely off, neutral and on, an annular stop member H0 is provided between the locking plate I00and the bottom of the recess 9|. 'Ihis'stop member IIO may comprise an apertured disc with stop fingers H2 and H5. extending perpendicularly at its periphery at spaced points. The inner periphery of the stop member has a series of. semi-circular indentationsor recessesarranged in circularpattern to receive the shanks of one or more securing screws II3 which may be provided to hold the lock member I00 to the body 90, in any desired angular position as in my Patent 2,451,224. Inassembling the device, the stop member H0 is placed with the stop finger II2 behind the locking tooth I02" and the stop finger II5 behind the lockingtooth I02. The

stop fingers I I2. and .I I5 are higher than the locking teeth and thus the rotation of the shaft is limited by the extension 95x coming into engagement with the or ges of one or another of the stop fingers H2 and H5.

Although in Fig. 3 I have illustrated a narrow tooth P32, it will be understood that this has been done mainly in order that it will not be necessary for the operator to turn the switch handle and shaft through an angle so large as would be necessary if the tooth H32; was made the same width as the teeth alongside it and the notch l 22% were also made as large as a full tooth width plus two spacings iii-3. It will he understood moreover that the location of the aised points upon the cam surfaces of the operating cams will also be so located that the contacts they control will be caused to close at the proper times when the shaft has been rotated. In the present in stance rotation through 22%? from off position should cause operation of the contacts while rotation through a 45 angle will cause operation of both the contacts and It will furthermore be obvious to those skilled in the art that if the stop finger i 55 were eliminated or located to be baclr. of another of the teeth on the lockm er ital. the rotation of the shaft could be increased he shaft could be held in any one of the additional positions thus provided by reason of the ability of the extension Qbrr to be located in another of the notches between the other teeth.

In addition to the foregoing, it should be noted that with the switch in the neutral position, i. e. with the extension 96x pressed by the springs it! against the side of the tooth 22 in the large notch mounted 152%, the handle can he pushed or struck to move the shaft axially, whereupon the spring Hi! bias will cause the switch to rotate toward off position. Then the spring (which the shaft axially into the position illustrated in Figs. 1 and 2) will relocate the switch in off position and lock it there.

Many modifications within the scope of my invention will occur to those skilled in the art. Therefore I do not limit it to the specific form and detail of the parts.

What I claim is:

1. In an electric switch, shaft, emannally moving shaft rotatively and axially, fixed means to loci: said shaft against rotation when the shaft is in one axial position, positioning means fixed on the shaft and engageahle with said locking means in said axial position but released from the locking means in an other axial position of the shaft permitting rotation of the shaft, fixed and movable contact means, means operated by rotation of the shaft to operate contact means selectively as said shaft is rotated into angularly spaced positions, yielding means acting to move said shaft toward a certain angular position, and means preventing return of said shaft from a second or third angular position to said certain angular position when said shaft is said one position but allowing rotary movement manually between a second and a third angular position.

2. In an electric switch, a shaft, means for manually moving said shaft rotatively and axially, fixed means to lock said shaft against rotation when the shaft is in a certain axial and anginlar position, positioning means fixed on the shaft and engageable with said locking means in said axial position but released from the locking means in another axial position of the shaft permitting rotation of the shaft, fixed and movable contact means, means operated by rotation of the shaft to operate said contact means selectively as said shaft is rotated into angularly spaced positions and means on said locking means engaged by said positioning means in said axial position but a different angular position of said shaft preventing return rotation to said certain angular position of said shaft, and yielding means automatically rotating said shaft from a third angular position to said different angular position when freed of manual control.

3. The switch as claimed in claim 2 having yielding means normally urging said shaft into said certain axial positioning and cooperating with said first-mentioned yielding means to return said shaft to said certain axial and angular positions when the shaft is moved axially to dis engage said locking and positioning means manually, without exerting rotative manual control.

4. In an electric switch, a shaft, means for manually moving said shaft rotatively axially, fixed and movable contact means, means op erated by rotation of the shaft into first, second and third positions to operate said contact means selectively, fixed means to lock said shaft against rotation when in said first position and in a cer tain axial position, positioning means fixed on the shaft and engageable with said locking means in said first position but movable axially to per mit rotation of the shaft after said axial move ment, means engaged by said positioning means to prevent rotation of the shaft between said second and said first rotative positions when in said certain axial position, but permitting rota tion between said second and third rotative positions.

5. A switch as claimed in claim 4 having means to bias said shaft into said certain axial position.

6. A switch as claimed in claim 5 having means to bias said shaft into said first rotative position, whereby when moved axially from said second position, it will automatically return to said first rotative and certain axial positions.

7. A switch as claimed in claim 4 having means to bias said shaft into said first rotative position.

DAVID W. JOHNSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,878,602 Ringbloom Sept. 20, 1932 2,426,306 Houck et a1 Aug. 26, 1947 2,451,224 Johnson Oct. 12, 1948 2,451,225 Johnson Oct. 12, 1948 

